to go within logic smite is just a long range creep killer excellent counter to tibbers who's presence actually does alot of damage. and ofcourse everyone loves to smite heimerdingers turrets in summoners rift. smite is a limited counter to few champions capable of killing minion based champions (Annie Malz Heimer and Yorick) and give that extra umph against pushers.

its not that smite is a competitive choice, but i would say its more viable then people are led to beleive

but the troll also got a GP executed with a Promoted+Blood Boiled minion. that made my night

I was playing Nunu like Nunu Bot in SR. Pushing 24/7, if I got attacked, just back off. And in the games I had with him, my pushing was so overwhelming that there was a constant 2 bottom, just to counter push me.

He's kind of fun to troll with as people completely underestimate the damage AP Nunu can do with just one offensive skill (his ult is just a big taunt). However if they smarten up and buy some mres, that's it for poor Nunu.